falter   verb [I]
 to lose strength or purpose and (almost) stop
 The dinner party conversation faltered for a moment.
 Her friends never faltered in their belief in her.
 Nigel's voice faltered and he stopped speaking.

 To falter is also to move uncertainly as if you might fall.
 The nurse saw him falter and made him lean on her.

 faltering   adjective
 This legislation is aimed at stimulating the faltering economy.
 The child's faltering words were sometimes hard to understand.

 falteringly   adverb